Pre Cooling HVAC & Cooling Units

Air conditioning systems are least efficient on the hottest days — exactly when they are needed most. On peak summer days, cooling capacity drops by 14–15% while power consumption rises by 31%. The cause is the condenser: as ambient air temperature climbs, heat exchange becomes less effective.

Applying a high-pressure misting system to the condenser inlet addresses this directly. The fine water mist lowers the temperature of air entering the condenser coil. On typical air-cooled chillers, a 6°C inlet air reduction produces around 14% efficiency improvement; at 12°C, gains reach 25–30%. Results vary with ambient humidity, but the effect is consistent under most operating conditions.

TECNOCOOLING high-pressure components are designed for integration into existing HVAC and refrigeration installations. Systems run at 70+ bar, producing droplets fine enough to evaporate before reaching the coil — no wetness, no corrosion risk.

Measured Results

• A 6°C reduction in condenser inlet air temperature delivers a 14% improvement in efficiency
• A 12°C reduction yields efficiency gains of 25–30%
• Energy savings of up to 30% on peak summer days
• Reduced wear and tear — fewer emergency callouts and longer equipment lifespan
• Prevents system failures during heatwaves when cooling demand is highest

Applications

TecnoCooling pre-cooling systems are used across Europe for:

• Industrial air-cooled chillers — production facilities, cold storage, data centres
• Rooftop HVAC units — offices, retail, logistics warehouses
• Refrigeration condensers — supermarkets, food processing, cold chain
• Data centre cooling — precision temperature control during peak loads

What Does HVAC Pre-Cooling Cost — and What Does It Save?

A high-pressure pre-cooling system for a single rooftop HVAC unit or chiller starts from approximately €2,500–€4,000 installed, including the pump unit, nozzle ring, RO filter and controls. For larger installations covering multiple condensers or chiller banks, systems are sized individually — typically €6,000–€18,000 for a multi-unit installation.

The return on investment is straightforward to calculate. A typical air-cooled chiller of 200 kW cooling capacity running 1,500 hours per summer at €0.20/kWh costs approximately €6,000 per season in energy. A 25% efficiency improvement from pre-cooling saves €1,500 per season — delivering payback on the system investment in 2–3 cooling seasons.

For data centres, supermarkets and cold chain operators where chillers run year-round in warm climates, payback periods of 12–18 months are common. Contact us for a site-specific ROI calculation based on your chiller specifications and local energy tariff.

Sector Spotlight: Industrial Chillers & Production Facilities

Industrial production facilities — aluminium smelters, plastics processors, food manufacturers — operate large air-cooled chillers that supply process cooling year-round. During summer, rising condenser temperatures reduce chiller capacity precisely when production heat loads are highest, leading to process interruptions and quality issues.

High-pressure pre-cooling at the condenser inlet restores rated capacity during peak summer conditions. Systems are typically installed on existing chiller frames without modification, and can be commissioned without shutting down the chiller. Automated controls activate the misting pump only when the ambient temperature exceeds the set threshold — typically 25°C — ensuring water is consumed only when the efficiency gain justifies it.

Our systems are active on industrial chillers at facilities including Hydro Extrusions, Indaver waste processing and food production sites across the Netherlands, Belgium and Spain.

Sector Spotlight: Commercial HVAC — Offices, Retail & Logistics

Commercial buildings with rooftop HVAC units face the same physics problem on a smaller scale. On a 35°C summer day, a rooftop unit designed for rated conditions at 25°C is operating outside its design envelope — consuming more energy and delivering less cooling to the occupied space below.

Pre-cooling nozzle rings are installed around the condenser section of each rooftop unit. The system connects to the building water supply via an RO filter, and activates automatically via a thermostat when outdoor temperature exceeds the set point. For a multi-tenant office building with 10 rooftop units, a complete system is typically installed in one day.

Facility managers and building owners report that pre-cooling also extends compressor service intervals — by reducing the number of hours equipment operates under thermal stress, the system reduces wear and lowers the frequency of emergency callouts during summer.

Legionella Prevention & Water Safety

Pre-cooling systems that spray water near air intakes require proper water management to prevent Legionella risk. Our systems address this through three design features: reverse osmosis filtration removes suspended particles and reduces bacterial nutrient load; anti-drip nozzles prevent standing water in the nozzle body between cycles; and automated drain-down valves empty the pipework when the system is inactive for extended periods.

System designs comply with Dutch ISSO 55 / BRL-K14010 guidelines and EU technical guidance on cooling water management. For facilities subject to mandatory water risk assessment (RIE water, Dutch Arbowet), we supply technical documentation describing the system design and risk control measures.

Why TecnoCooling?

Our systems are engineered and manufactured in Italy with over 38 years of experience. Operating at 70–120 bar, the mist droplet size is so fine that surfaces remain dry while the cooling effect is immediate. Systems are designed for easy installation by any technical service team, with 24/7 support available.

Trusted by leading companies including Hydro Extrusions, McDonald’s, Indaver and many more across Europe.

Frequently Asked Questions

Does the mist wet the condenser fins?
No. At 70–120 bar, droplet size is below 10 microns — the mist evaporates completely before reaching the condenser.

What water quality is required?
We recommend using a reverse osmosis filter to prevent mineral deposits on nozzles and fins. Filter sets are available as part of our system packages.

How quickly can a system be installed?
Most HVAC pre-cooling installations are completed within 1–2 days by a standard technical team. Full documentation and video support is provided.

Can the system be installed without shutting down the HVAC unit?
Yes. In most cases the nozzle ring and pipework are installed around the condenser section while the unit remains operational. The pump and controls are connected to the water supply and electrical supply separately. Commissioning — including pressure testing and nozzle adjustment — takes 2–4 hours and does not require a shutdown.

What happens to the system in winter?
In temperate climates, the system is inactive during the winter months. Before the first frost, the pipework and pump should be drained and blown through with compressed air. Anti-freeze protection for the pump can also be specified for year-round installations in cold climates. In warmer regions (Spain, Portugal, southern France), systems may operate year-round where summer conditions persist.

Is the system suitable for heat pumps as well as chillers?
Yes. The same pre-cooling principle applies to air-source heat pumps operating in cooling mode. By reducing the condenser inlet temperature, the heat pump COP improves during hot weather — the same efficiency gain as with conventional chillers. Contact our engineering team for heat pump specific sizing guidance.

Interested in distributing or installing TECNOCOOLING misting solutions? Fogsystems.eu supplies dealers and installers across Europe with professional-grade high-pressure components. Contact us for dealer pricing and technical documentation.